Abstract: Social host policies focused on underage drinking parties are implemented to reduce social availability of alcohol and high-risk drinking by adolescents in private locations. We examined the policies’ relationship with drinking location, peer-group drinking size, heavy episodic drinking, and nonviolent consequences. Cross-sectional data from 11,205, 14–20-year olds, were analyzed using multilevel modeling. Policies were not associated with drinking location, decreased heavy episodic drinking, or nonviolent consequences. However, adolescents from communities with a preexisting policy had lower odds of drinking in large peer groups compared to those from communities without a policy at baseline. Additional research is needed to examine their effectiveness. The study's limitations are noted.